How a Sealed Telecom Cabinet Rejects Heat without Mixing Air
A sealed telecom cabinet can reject heat through an air-to-air heat exchanger without drawing outdoor air through its electronics. Two separate fan-driven circuits meet at a heat-transfer core, not an open air passage.
Follow the air through the process
The cabinet fan collects internal heat
The internal fan moves cabinet air past the equipment and into one set of core channels. That same air returns to the cabinet. It does not cross into the outdoor circuit.
Heat crosses the separating wall
Inside the core, heat passes through thin separating walls into neighboring channels. The air streams remain apart: the wall transfers heat while preserving their physical separation.
The outside fan completes heat rejection
A second fan draws outdoor air through the other channels and discharges the warmed air outside. Its inlet and outlet must stay clear so the outside circuit does not keep reusing its own hot discharge.
The temperature difference matters
This air-to-air core needs outdoor air cooler than the cabinet air to reject heat. As the temperature difference shrinks, its available cooling falls. It cannot provide refrigeration below ambient temperature.
Airflow function
- In the separate cabinet and outdoor circuits on either side of the air-to-air heat exchanger.
- Compact DC axial families can be considered for the space and duty of each circuit. Both sides need adequate airflow; their pressure losses and environmental exposure may differ.
What can change the result
- The outside circuit recirculates its warmed discharge.
- Blocked core passages restrict one air circuit.
- Leaking seals mix air that should remain separated.
Start with the complete air path
Share your layout and the information you already have. Unknown values can be identified before a configuration is selected.
Match the fan to this air path
Discuss LONGWELL compact DC axial fans for each circuit's airflow, pressure and space. Confirm control, environmental protection and the completed exchanger duty for the application.
Where it sits
In the separate cabinet and outdoor circuits on either side of the air-to-air heat exchanger.
Why consider this configuration
Compact DC axial families can be considered for the space and duty of each circuit. Both sides need adequate airflow; their pressure losses and environmental exposure may differ.
Check the result in your equipment
Discuss both cabinet fan duties
Send cabinet heat load, maximum cabinet and outdoor temperature, internal-circuit pressure and flow, external-circuit pressure and flow, fan size, power and control, core sealing and environmental protection. Ask LONGWELL to review a suitable configuration, fan curve, drawing and control details. A layout or existing fan model can start the review.
A layout, installation photos or your existing model is enough to start the discussion.